# v20.2.1 Tentacle released

DevFeed: [v20.2.1 Tentacle released](<https://devfeed.tech/articles/v20-2-1-tentacle-released-12342.md>)

Original publisher: [Read original article](<https://ceph.io/en/news/blog/2026/v20-2-1-tentacle-released/>)

Author: Yuri Weinstein

Published: 2026-04-06T00:00:00Z

Content type: release

Language: en

Sources: [Ceph Blog](<https://devfeed.tech/sources/ceph-blog.md>)

Topics: [bug](<https://devfeed.tech/topics/bug.md>), [configuration](<https://devfeed.tech/topics/configuration.md>), [monitor](<https://devfeed.tech/topics/monitor.md>), [Command-line interface](<https://devfeed.tech/topics/cli.md>), [API](<https://devfeed.tech/topics/api.md>), [dashboards](<https://devfeed.tech/topics/dashboards.md>), [JSON](<https://devfeed.tech/topics/json.md>)

Tags: [2026](<https://devfeed.tech/tags/2026.md>), [api](<https://devfeed.tech/tags/api.md>), [blog-post](<https://devfeed.tech/tags/blog-post.md>), [bug](<https://devfeed.tech/tags/bug.md>), [cli](<https://devfeed.tech/tags/cli.md>), [en-article](<https://devfeed.tech/tags/en-article.md>), [en-blog-post](<https://devfeed.tech/tags/en-blog-post.md>), [json](<https://devfeed.tech/tags/json.md>), [monitor](<https://devfeed.tech/tags/monitor.md>), [nvme](<https://devfeed.tech/tags/nvme.md>), [osd](<https://devfeed.tech/tags/osd.md>), [peering](<https://devfeed.tech/tags/peering.md>), [policy](<https://devfeed.tech/tags/policy.md>), [recovery](<https://devfeed.tech/tags/recovery.md>), [reef](<https://devfeed.tech/tags/reef.md>), [release](<https://devfeed.tech/tags/release.md>), [rgw](<https://devfeed.tech/tags/rgw.md>), [tentacle](<https://devfeed.tech/tags/tentacle.md>), [ui](<https://devfeed.tech/tags/ui.md>), [workflows](<https://devfeed.tech/tags/workflows.md>)

## AI overview

Ceph v20.2.1, the first minor release in the Tentacle series, is recommended for all users. The release fixes storage, recovery, peering, validation, and dashboard issues; restricts unsafe fast EC configurations; improves NVMeoF Gateway failover; adds listener and subsystem CLI commands; introduces a transient exclusive RBD lock policy; and updates dashboard navigation and forms.

## Source excerpt

This is the first minor release in the Tentacle series. We recommend that all users update to this release. Release Date ¶ April 06, 2026 Notable Changes ¶ OSD / BlueStore ¶ EC Recovery: Fixed a length calculation bug in erase_after_ro_offset() that caused empty shards to retain data, leading to shard_size >= tobj_size assertion failures when recovering small objects in EC pools. BlueFS Volume Selector: Updated the BlueFS volume selector to properly account for file size changes when recovering the WAL in envelope mode. BlueFS: Fixed a bug where stat() missed the actual file size update after indexing WAL envelope files. Monitor (mon) ¶ Fast EC Restrictions: Denied the ability to enable EC optimizations ("fast EC") for non-4K-aligned chunk sizes. Unaligned chunk sizes handled by fast EC perform poorly and suffer from bugs, so attempts to force this configuration are now rejected. Peering: Ensured ceph pg repeer proposes a correctly sized pg temp, as optimized EC cannot cope with mismatched sizes. NVMeoF Gateway: Added a new nvme-gw listeners command to display all existing listeners (including auto-listeners) inside a pool/group. NVMeoF Failover: Overhauled the NVMeoF Gateway fast-failover logic. Beacon timeouts are now evaluated within prepare_beacon to support shorter intervals, and the mechanism for detecting monitor slowness was improved. librbd & rbd-mirror ¶ RBD: Introduced a new RBD_LOCK_MODE_EXCLUSIVE_TRANSIENT policy for rbd_lock_acquire(). This is a low-level interface intended to allow a peer to grab exclusive lock manually for short periods of time with other peers pausing their activity and waiting for the lock to be released rather than instantly aborting I/O and returning an error. It's possible to switch from RBD_LOCK_MODE_EXCLUSIVE to RBD_LOCK_MODE_EXCLUSIVE_TRANSIENT policy and vice versa even if the lock is already held. Ceph Object Gateway (RGW) ¶ Multi-Part Operations: Fixed conditional validation handling in MultiWrite, Delete, and MultiDelete